print('range 10: ', range(10))
alist = list(range(10))
print('alist: ',alist)

alist = list(range(6, 10))
print(alist)

alist = list(range(1, 10, 2))
print(alist)

alist = list(range(10, 0, -1))
print(alist)

sum100 = 0
for i in range(1, 101):
    sum100 += i
print('sum100:', sum100)